Okay, we all know that in movies if you crash your car into a tree it must expode in a fancy ball of fire.
Likewise, shoot someone with any kind of firearm and they go flying 20 feet through the air. The most dramatic movie weapon is the shotgun – two barrels at point blank range sends the bad-guy/vampire/zombie/alien flying 50 feet through the air and crashing through a plate glass window.
Fact-based question: What is the concussive force of a shotgun blast actually like?
I assume that if a double barrel shotgun could send a 250 lb hockey-mask-wearing zombie flying 30 feet, the recoil would knock down the shooter too.
What’s the straight dope? How much of a punch does a shotgun have in real life?
(Clearly, I’ve never fired a shotgun, hence I need to ask the gun-totin’ Dopers.)
By Newton’s Third Law, the force of being hit by a shotgun blast is approximately equal to the ‘recoil’ force that you feel when firing a shotgun, less a small amount of aerodynamic drag.
Even if you didn’t brace yourself, the recoil of a shotgun probably would be enough to knock you over, let alone send you flying 50 ft.
That’s what I figured. The movies makes it look like the zombie was hit with a canonball, while the Hero stands perfectly still. Always seemed ridiculous to me, “suspension of disbelief” notwithstanding.
Still I’m curious to know what the power of a shotgun really is – even if it’s just a relative anecdote like “Mike Tyson punch” or “hit by car” or “belly flop on water from the high diving board.” – though I’d be happy with force/mass/acceleration type answer too.
I thought that the ammunition was mostly some kind of buckshot that perforates the target rather than pounds it.
Just stating Newton’s third law is correct but may be misleading. Remember that when you fire a shotgun shell there is typically a shotgun involved. You have a system. Lead comes out one and and on the other the base of the shell pushes against the breechface of the shotgun which in turn pushes against the shooter. A typical 12 gauge shotgun shell might have 1-1/8 ounces of lead shot plus a plastic wad coming out the end. The shotgun itself will weigh several pounds. The reaction of the shotgun pressing against the shooter’s shoulder is somewhat more gentler than the shot hitting the bad guy/zombie/steel plate pepper popper/wild turkey (the actual bird, not the whiskey - who shoots at whiskey?). The mass of the weapon has a dramatic effect on felt recoil. If you fire a 12 gauge derringer you’ll soon be known as lefty.
Still an ounce and an eigth of lead moving at maybe 800 feet per second (a WAG, I haven’t consulted my reloading manuals) isn’t going to send a 210kg hockey mask zombie flying even with a perfectly elastic collision.
Sorry, I meant wouldn’t be enough to knock you over.
I do remember the very first time a fired a gun (it was a 12 gage single-barrel shotgun), when I was very young and did not know about Newton’s Third Law. The recoil came as a complete surprise to me, forcing the stock into my shoulder and leaving a large bruise where it hit.
Based not on physics, but on having hunted animals and birds with a shotgun when I was young – no, it won’t send a large man flying. On the other hand, it will mess him up way worse than you see in the movies, if you’re shooting at close range. All those pellets blasting into flesh, when the distance hasn’t been enough for them to scatter ----yecch.
You are now involving what they call terminal ballistics. Mike Tyson does not deliver his punches with a small mass of lead balls but through a big, padded boxing glove (in the ring anyway). This distributes the force of the punch through a large area and does a better job of transferring momentum into the target. If Mike had his hand replaced with a 3/4" steel rod and he punched you in the chest you’d get very different results. Consider the bean bags that law enforcement use to deliver an Iron Mike™ punch to recalcitrent bad guys. I’m not sure what charge is used in the cartridge but it may have similar momentum to a normal shotshell but would have very different terminal ballstics. Bad guy will probably get knocked down due to trauma as well as force but still won’t go flying.
My velocity WAG was way off as I usually load black powder shotshells. Muzzle velocities for 12ga, 1-1/8 oz of shot run from 1,100-1,400 feet per second. Do your own momentum calculations with mass/velocity as kinetic energy may give you some misleading numbers.
Without having run all of the necessary calculations, I’d say that the effect of the momemtum alone of being hit point-blank by a typical 12-ga. double-barrel shotgun blast would be about what you might feel if you gave a seven-year-old boy an adult-sized baseball bat and had him hit you with it as hard as he possibly could.
It would definitely stun you, and you could be knocked down by it, but I don’t think it could get you airborne.
Even a fairly large shotgun still weighs considerably less than a full-grown human, correct?
If I’m shooting another fellow on the Moon (so we don’t have air resistance), and he weighs exactly as much as my weight plus the weight of the gun, and all of the pellets hit him and lodge in his body, then he will have exactly the same momentum and velocity imparted to him as I have imparted to me. Hence, the best comparison for the impact felt is “the same as the recoil you feel”. Or, if you wish to take into account that the shooter is probably better prepared than the target, then make the comparison “the same as the recoil you felt the first time you shot”.
No, it would damage Jason rather badly. I just googled “shotgun wound” images to show that these things are serious, and decided NOT to link. Do not look if you can’t be clinical.
Interesting that so many posters never seem to have actually fired a shotgun. My wife hasn’t either and I’ve offered to show her how, but she has not interest.
As has been pointed out, firing a 12 gauge shotgun, even with 00 buckshot, won’t knock you over. It will, however, seriously disfigure anything that the shot hits (particularly at close range). IIRC, there are only 4 or 6 pieces of shot in 00 buckshot.
Waterfowl hunters on the Chesapeake Bay used to use what were called “punt guns.” They were esstentially home-made guns consisting of a piece of pipe with a firing mechanism. The barrell set out over the bow of a skiff, the “gun” was filled with nails, scrap, even rocks, and fired into flocks of birds (this was to take down as many birds as possible for sale to wholesalers). My grandfather had a punt gun that was about 10 feet long and even had a stock, even though it was designed to be held to the shoulder.
IIRC, 10 gauge shotguns are still made, and some companies used to make 6 and 8 gauge, but I’ve never seen one.